High-performance signal-friendly solar-control films

Abstract

Solar-control films are disclosed that include a first dielectric stack having: alternating layers of high and low refractive index materials of a first equal optical thickness; and at least one layer that is an odd multiple of the first equal optical thickness, wherein the first dielectric stack has a reflection band centered at a wavelength from 800 nm to 1500 nm; and a second dielectric stack, optically adjacent the first dielectric stack, having: alternating layers of high and low refractive index materials of a second equal optical thickness; and at least a single layer that is an even multiple of the second equal optical thickness.

1 . A solar-control film, comprising:
 a. a first dielectric stack having:
 i. alternating layers of high and low refractive index materials of a first equal optical thickness; and 
 ii. at least one layer that is an odd multiple of the first equal optical thickness, 
 wherein the first dielectric stack has a reflection band centered at a wavelength from 800 nm to 1500 nm; and 
   b. a second dielectric stack, optically adjacent the first dielectric stack, having:
 i. alternating layers of high and low refractive index materials of a second equal optical thickness; and 
 ii. at least a single layer that is an even multiple of the second equal optical thickness, causing a double peak reflection band that is at least as wide as the reflection band of the first dielectric reflector stack, and that exhibits both a first peak and a second peak at a wavelength range from 800 nm to 1500 nm. 
   
     
     
         2 . The solar-control film of  claim 1 , wherein the solar-control film reflects at least 30% of electromagnetic waves over a wavelength range from 850 nm to 1500 nm. 
     
     
         3 . The solar-control film of  claim 1 , wherein the solar-control film reflects at least 30% of electromagnetic waves over a 600 nm wavelength range. 
     
     
         4 . The solar-control film of  claim 1 , further comprising c) a color-correcting layer comprising at least two alternating layers of high and low refractive indices in which the optical thickness of each layer is less than about a one-eighth wave thickness. 
     
     
         5 . The solar-control film of  claim 1 , further comprising c) a color-correcting layer comprising at least two alternating layers of high and low refractive indices in which the optical thickness of each layer is less than about a one-sixteenth wave thickness. 
     
     
         6 . The solar-control film of  claim 1 , wherein a peak of the reflection band of the first dielectric stack falls between the first peak and the second peak of the reflection band of the second dielectric stack. 
     
     
         7 . The solar-control film of  claim 1 , wherein the solar-control film transmits at least 90% of radio frequency wavelengths. 
     
     
         8 . The solar-control film of  claim 1 , wherein the solar-control film exhibits a Tvis of at least 70%. 
     
     
         9 . The solar-control film of  claim 1 , wherein the odd multiple of the first equal optical thickness is a multiple selected from 1, 3, 5, 7, or 9. 
     
     
         10 . The solar-control film of  claim 1 , wherein the even multiple of the second equal optical thickness is a multiple selected from 2, 4, 6, 8, or 10. 
     
     
         11 . The solar-control film of  claim 1 , wherein the at least one layer that is an odd multiple of the first equal optical thickness is a single optical thickness. 
     
     
         12 . The solar-control film of  claim 1 , wherein the single layer that is an even multiple of the second equal optical thickness is double the equal optical thickness. 
     
     
         13 . The solar-control film of  claim 1 , wherein the solar-control film reflects at least 50% of electromagnetic waves over a wavelength range from 800 nm to 1500 nm. 
     
     
         14 . The solar-control film of  claim 1 , wherein the solar-control film exhibits a Tvis of at least 80%. 
     
     
         15 . The solar-control film of  claim 1 , wherein the first dielectric reflector stack and the second dielectric reflector stack are deposited on the same substrate. 
     
     
         16 . The solar-control film of  claim 1 , wherein the first dielectric reflector stack and the second dielectric reflector stack are deposited on separate substrates that are laminated to form the solar-control film. 
     
     
         17 . The solar-control film of  claim 1 , wherein the first dielectric reflector stack comprises from 3 to 11 layers. 
     
     
         18 . The solar-control film of  claim 1 , wherein the second dielectric reflector stack comprises from 5 to 11 layers, and wherein the single layer that is an even multiple of the second equal optical thickness is one of three middle layers. 
     
     
         19 . The solar-control film of  claim 1 , wherein the broad-band reflecting film exhibits a solar reflection of at least 20%. 
     
     
         20 . The solar-control film of  claim 1 , wherein the layers of high refractive index materials have a refractive index of at least 2. 
     
     
         21 . The solar-control film of  claim 1 , wherein the layers of low refractive index materials have a refractive index of less than 1.5. 
     
     
         22 . The solar-control film of  claim 1 , wherein the layers of high refractive index materials comprise one or more of: titanium oxides, niobium oxides, indium oxides, tantalum oxides, zinc sulfides, gallium nitrides. 
     
     
         23 . The solar-control film of  claim 1 , wherein the layers of low refractive index materials comprise one or more of: silicon dioxides, magnesium fluorides, or calcium fluorides. 
     
     
         24 . The solar-control film of  claim 1 , wherein the solar-control film reflects at least 70% of the electromagnetic waves over a wavelength range in the infrared from about 850 nm to about 1350 nm, and at least 50% of the electromagnetic waves over a wavelength range in the infrared from about 800 nm to about 1500 nm. 
     
     
         25 . The solar-control film of  claim 1 , wherein the repeating layers of high and low refractive index materials of the first dielectric reflector stack are polymer layers.